Because nothing is 100% efficient so you would always need more power to turn the alternator than it is capable of generating. You could, in theory, use an electric motor to turn a generator which would produce the power to turn the motor so you'd have a perpetual motion machine, something that would continue spinning all day long. But it won't because to generate the amount of power needed to turn the motor the generator would need more power than the motor can supply. You never get anything for nothing.
Some of these EV beasties have 'Regenerative Braking' of course although I suspect that's more of a gimmick than anything.....
But of course you could have a wind turbine on top to 'charge up whilst parked up' (if there is handy breeze,..) ?
Or maybe not: (only 80W in a gale): https://www.emarineinc.com/rutland-504-12-volt-wind-turbine
Damnit Gilbert. I knew you'd ruin it. Lol. I thought I was on to something there.
How about constantly rubbing the battery then? Works on a tv remote!
The regenerative braking means that instead of a mechanical brake they use the movement to turn a generator to produce a tiny bit more electricity to put back into the battery, the drag caused by turning the generator acts as the brake instead. The latest thing that has been pointed out is that with the particulates in exhaust emissions being reduced more and more they have realised that there are particulates being produced by the friction of the tyres on the road and from brake pads. So the next step is likely to be tyres that never wear out (and therefore won't be capable of giving any grip) and electronic braking (but that needs more electricity so you'd reduce the range not only when driving but when stopping too).
No, rubbing the battery in your TV remote just warms it up a bit to squeeze the last millivolt out of it. Which makes me wonder what will happen to an electric car in the dead of winter if you let the battery go completely flat. We had some kit at work where the battery pack consisted of a pair of Lithium cells. In the pack was also the charging circuit but that had to be powered so was connected to one of the batteries. If the batteries were both drained and the kit not used for a while, it wasn't possible to charge the battery as there wasn't enough power in the one to power the charging circuitry. We would have to open the pack up and swap the internal batteries over and hope the other one hadn't been drained completely and had enough in it to power it. If that one was also completely flat, we'd sit them on a radiator for an hour or so to squeeze a tiny bit of power out of them so that the charging circuit would work. For the same reason the battery in your laptop doesn't have just a positive and negative terminal, it has two or three other connections that go to the charging circuitry. So what will happen in the cold with a completely discharged Lithium battery in an electric car?
Incidentally, Gordon's comment earlier about pollution rising when the emissions crap was fitted may hold more than a little truth. We all know how bad a modern diesel stinks but I've currently got a series 1 Discovery here with the old 200 TDi engine. So no cats or particulate filters. While the exhaust fumes from that still smell like diesel exhaust, they don't burn your eyes or have the Hydrogen Sulphide smell like the stench that comes from a VAG TDi for example.
In my last years of service we were invited (being a semi-governmental company) to test EV's as company cars. We got hold of a Mitsubishi I-MIEV and a VW UP.
The first one claimed to have a range of 125 kms, in practice after 40 kms the socket sign already lit on the dash and was a disaster at speeds over 70 km/hr.
Far to high gravity point, the car felt like being made of underwear elastic. It had a selector to choose the charging mode when releasing the throttle, A and B.
The firmest was B, when leaving a motorway at the exit it really braked and probably charged the batteries, until I saw a car coming up in the mirror making an emergency brake avoiding hitting me, no brake lights!
The VW UP felt like a kit car, pleasure to drive and had effectively a range of 130 kms.
We used them in the city centre of Amsterdam where we had to reach metrostations, sometimes in pedestrians area's. Highly dangerous, even at speeds up to 5 km/hr. Keep your foot above the brake because people don't hear you coming.
Gilbertd wrote:
Because nothing is 100% efficient so you would always need more power to turn the alternator than it is capable of generating. You could, in theory, use an electric motor to turn a generator which would produce the power to turn the motor so you'd have a perpetual motion machine, something that would continue spinning all day long. But it won't because to generate the amount of power needed to turn the motor the generator would need more power than the motor can supply. You never get anything for nothing.
Almost the same with those hydrogen generation systems you can buy to fit to your car. They run on electric,generated by the alternator to turn water into hydrogen which, they reckon, in turn makes the engine more powerful and economical when it is fed as fuel to the engine. But there's no way that can work, except on a really inefficient old diesel where the addition of a bit of hydrogen increases the efficiency at which the engine burns the diesel. Over the years I have been approached by many firms who wanted to work in partnership with me on this type of hydrogen supplementation system (me doing all the fitting and, apparently, most of the tech sales talk too). I turned them all down except to tell them that I would fit them if they found an owner who was dead set on having such system fitted, but even then I wouldn't recommend such a gimmick or plug it's 'merits' even to their already convinced customer. They all missed the point that it takes more power from the alternator to make the hydrogen than could be gained by burning it even if the engine was 100% efficient.
Hehhe. I guess if they could demonstrate that the alternator was taking X% of the engine output to generate Hyrdrogen which boosted the engine by >X% at the same load they'd have a case.
Bet they didn't though :)
Lpgc wrote:
The concept of charging a different rate for electricity depending on time of day has been fairly mainstream since 'Economy7'. I'm probably a bit young at 47 to have been directly affected but over the years governments and various energy firms have tried to push some implausible schemes on the public including Economy7, 'Come home to a real coal fire', 'Heat electric', 'Save it', etc. But I was under the belief smart meters were a necessity of the solar panel electric sell back to grid scheme, and solar panels partly due to the Kyoto Agreement. Another one of those types of agreements UK governments sign up to and then stick to when other country governments sign up but don't stick to the agreement unless it works in their countries interests. I remember when coke (from coal) was seen as the way forward - It did improve air quality in a lot of areas but too bad for those living near coking plants lol.. 7 Miles from me there was a coking plant and when the wind was in the wrong direction, the plant working in a certain way, it stunk from that distance. When I first started driving and went anywhere near it I'd put my car heater on recirc (Cortina, no aircon). All this leccy has to be made somewhere and (as Gilbert mentioned) it has to be shifted via better electrical infrastructure than we currently have...
Simon
The thing is with the smart meter ideas it would tie into several different rates throughout the day - if you've ever experienced economy 10 you will know this is likely to be more hassle than benefit. I'm on Economy 7 here due to no mains gas, thats fairly simple (although its still complicated enough for Scottish power to completely balls it up...) My mates flat was on economy 10 , every time the weather started to turn cold and you wanted the heating on (storage heaters again as no gas to the property) it was a gamble when setting them if they would work or not, and if not he had to get on the phone to Eon to get them to come and sort it out. After the 3rd set of meters to the 3 flats they swapped them all for Economy 7 ones.
From what he was told the economy 10 meters have 4 different rates on them, which are switched on by a radio signal? either way this seemed to be a very unreliable way of doing it going by the amount of visits he had to have to sort it out.
Morat wrote:
Hehhe. I guess if they could demonstrate that the alternator was taking X% of the engine output to generate Hyrdrogen which boosted the engine by >X% at the same load they'd have a case.
Bet they didn't though :)
Some of them are conspiracy theorists and reckon it's been possible to run cars on 100% hydrogen generated by a big enough alternator on the engine for many years, except oil companies suppressed the technology! There's no telling most of them - Point out that the little bubbles of hydrogen their systems make wouldn't be 1/10000th of enough hydrogen to run the engine on and they talk about up-scaling their systems. Point out that their systems currently draw maybe an amp (by their own reckoning) and 10000amps at 12v would be 120000 watts (or 161hp), from a system that even on this scale is only capable of providing enough gas for a 100bhp engine and they reckon you're part of the conspiracy or that you must be missing something! One 'firm' told me it works the same way as power from a hydrogen bomb and nobody understands how an H bomb works!,So I explained how a H bomb works lol. Very loose figures provided by me here but I did go to the length of doing the sums properly at the time.
On Porth Beach Newquay campsite as I write, surrounded by VW campervans, half of which are actually just VW vans with sleeping bags chucked in the back. I don't get the following VW enjoy... Maybe at one time if someone wanted a German engineered vehicle they might be the first/only choice, but these days? Maybe given the emissions scandal there might one day be a callback on VW's - bring in your TDI smogmotion and we'll swap out the engine for an electric motor lol! Maybe they have such a great following because people still admire the bloke who inspired the marque... then again maybe not.
Lpgc wrote:
On Porth Beach Newquay campsite as I write, surrounded by VW campervans...
Now that's brave- you're about to be inundated with kiddies (and older kiddies) hitting the Boardmasters festival, starting from tomorrow. It's become one of those rites of passage for anyone aged 15 to 25 from anywhere in the south west, Only a small minority have any interest in surfing (or VW vans), and the roads are rammed with tottering teenies, parents dumping them off, picking them up, that sort of thing.
Enjoy!
Lpgc wrote:
Some of them are conspiracy theorists and reckon it's been possible to run cars on 100% hydrogen generated by a big enough alternator on the engine for many years, except oil companies suppressed the technology! There's no telling most of them - Point out that the little bubbles of hydrogen their systems make wouldn't be 1/10000th of enough hydrogen to run the engine on and they talk about up-scaling their systems.
I did some numbers on it based on half-remembered O-grade Chemistry from nearly 30 years ago and some creative misunderstanding of car engines. You can read it here and please feel free to point out everything that's wrong with it.
Some very impressive science/calculations there Gordon ! Never thought I would see an explanation with a P38 and Hydrogen mentioned either !
The main problem is we are again back in 'perpetual motion territory', ie we would need a HUGE alternator/regulator to produce enough energy to electrolytically split enough water to H/02 in the first case... and that alternator would thus increase engine load (and fuel consumption) considerably - as Morat has previously stated....
Of course we could 'just' use a small on-board nuclear reactor to supply power to the electrolysis process instead....? ( just don't tell the H&SE !!)
How about this instead: https://en.wikipedia.org/wiki/Ford_Nucleon
No mention there of 'glow-in-the-dark' drivers though....
Lots of comments since i last looked and i dont have time to read it all in detail.
I had a similar issue with my boss at work, He was concerned that people might start bitching about how i was getting "free fuel" and they werent allowed free petrol. But being a decent place they said "we'll simply install a meter, and you pay for what you use". The reality is the amount of energy the car draws is trivial. It costs about 30p an hour while charging (16A single phase) and its usually re-filled what i use by lunch time. So its about £1.20. And sure, it adds up, but its inconsequential compared with the other operational costs of the building. Theres also a BIK issue, which is alleviated by installing the meter.
Up here in scotland the councils have free charging points all over the country. No limits on use, no cost to charge. Wont last forever ofcourse, but its a nice perk for now.
The regenerative braking does make a difference, especially in stop start type traffic, as you can recapture a lot of the energy you'd otherwise be throwing away. Theres a maximum charge limit though, so you cant capture it all unless you alter your driving style to suit. Some people can perfect 1 pedal driving, using no brakes at all (well most of the time anyway).